CHAPTER II.

HOW THE QUAINT OLD FISHES OF ANCIENT TIMES HAVE LIVED ON INTO OUR DAY 20

PICTURE-HEADING--Ideal restoration of _Pterygotus_, the huge extinct sea-scorpion nine feet long; with the earliest known fish _Pteraspis_, _Cephalaspis_, and small shark-like animals swimming among Stone-lilies, Trilobites, etc. (From various sources.)